<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Hulk</title>
</head>
<body>
    <p>改变背景颜色，请点击改变颜色按钮改变当前页面背景颜色为绿色</p>
    <button id="changeColorButton">改变背景颜色</button>
    <script src="popup.js"></script>
</body>
</html>